Dr. Sekizawa graduated from Showa University School of Medicine in 1988 and then majored in obstetrics and gynecology. In 1997, he studied at Prof. Diana W Bianchi's laboratory at the New England Medical Center, where he was engaged in research on prenatal genetic testing using maternal blood. After that, he returned to Japan and continued his research, including research on the prediction of preeclampsia. In 2013, became the chief professor of the Department of Obstetrics and Gynecology, Showa University School of Medicine.